/Engine/Source/Runtime/NavigationSystem/Public/NavLinkCustomComponent.h
Add box obstacle during generation of navigation data this can be used to create empty area under doors
void AddNavigationObstacle ( [TSubclassOf](API\Runtime\CoreUObject\Templates\TSubclassOf)< [UNavArea](API\Runtime\NavigationSystem\NavAreas\UNavArea) > AreaClass, const FVector & BoxExtent, const FVector & BoxOffset )